Hilti Kwik HUS-EZ Concrete and Masonry Screw Anchor - Carbon Steel - KH-EZ 3/8" x 1-7/8" - 418055 - Box of 50 Especially suited for Seismic and Cracked Concrete Applications, as well as Grout-Filled CMU Blocks. Seismic Qualifications Tested in Accordance with ICC-ES AC 193 and AC 106. Quick and Easy to Install, with no High-Accuracy Torque Wrench Required and No Hammering. Optimized Thread Design for Best-in-Class Setting Performance and Superior Load Values. For Use with Standard ANSI-Tolerance Drill Bit; No Special Tolerance Drill Bits Required.